Kaspersky beats Zango in malware classification case

Kaspersky Lab has secured a legal victory against notorious adware firm Zango, with a ruling that goes a long way towards protecting security software developers from nuisance lawsuits from the developers of internet pests in future.

The judgment might also protects security researchers from legal threats when disclosing vulnerabilities.

The 9th US Circuit Court of Appeals ruled that Kaspersky Lab was within its rights to develop technology that interfered with the operation of Zango's crudware. Zango argued that defining its software as malware interfered with its ability to do business with its "customers", but the judges ruled that Kaspersky was entitled to immunity under provision within the Communications Decency Act (CDA), as a provider of "interactive computer services".

Zango sued Kaspersky Lab in a failed bid to oblige the security firm to reclassify its adware software as benign, allowing what were previously classified as potentially undesirable programs to operate unimpeded. The appeals court backed a lower court ruling that Kaspersky was entitled to classify Zango's software as potentially malign, in a judgment praised by the Russian security software and services firm.

The ruling protects a consumer’s choice to determine what information and software is allowed on their computing systems, and protects the ability of anti-malware vendors to identify and label software programs that may be potentially unwanted and harmful to computer users. Kaspersky Lab's software is designed to do just that. Users can adjust the settings to allow certain programs of their choice to come through at all times.

Zango, whose software was also listed as adware by Symantec and McAfee, went tits-up in April, so it isn't around to contest the ruling. The firm sued both Kaspersky Labs and PC Tools (now part of Symantec) over alleged interference with its business and trade libel back in May 2007.

The PC Tools lawsuit was quickly rejected by a judge but the same complaints against Kaspersky took much longer to resolve, amid legal wrangling over whether the Russian firm provided a product or a service. Only a service was clearly within the safe harbour provisions of the CDA and anti-virus updates meant that Kaspersky's technology qualified as a service, appeal court judges decided, in rejecting one of the grounds of Zango's appeal.

The Kaspersky ruling was welcomed by other security firms. SecureWorks notes that "Good Samaritan" blocking of offensive material is included as a safe harbour provision in the Communications Decency Act, alongside better-known rules that protect US ISPs from getting into trouble for anything their users say online.

SecureWorks goes on to argue that the Good Samaritan provisions that helped Kaspersky might also extend to security researchers who publish vulnerability information, especially where this information helps in the development of countermeasures. That's a piece of reasoning based on theory not on actual case law, as SecureWorks notes.

In a nod to controversy over news that at scheduled presentation on ATM (cash machine) security at BlackHat has been pulled at the last minute. Nick Chapman of SecureWorks concludes: "It would be nice to have another tool to defend against legal threats that have unfortunately prevented some security talks." ®